I do not think so. A data dictionary would have validation ("ZIP codes
are five digits") and verification ("ZIP codes and states match up this
way!") modeled in it. There would be external data sources ("we buy
ZIP data tapes from the USPS every six months"). There would be syntax
rules ("the following suffixes are allowed on data element names..").
Etc.

I have done a schema for DFD which was a lot of meta-data type stuff
("a process must have at least one inflow, and at least one outflow",
"In and out flows must balance at all levels of abstraction", etc.)
But that is not what we have here.